Telegraphy



(No'Model.) i. 4 4 l?. B.`DBLANY.

TBLBGRAPHY. l

Patented Deo. 5, 1893.

NrTED STATES PATENT OFFICE.

PATRICK BERNARD DELANY, OF SOUTH ORANGE, NEW JERSEY.

TELEGRAPHY.

SPECIFICATION forming part of Letters Patent No. 510,002, dated December5, 1893.

Application filed July 25, 1891. Serial No. l00.74% (No model.)

To all whom t may concern.-

Beit known that I, PATRICK BERNARD DE- LANY, a citizen of the UnitedStates, residing at South Orange, in the county of Essex and State ofNew Jersey, have invented certain :mating polarity and of uniformlyequal dura` tion, may be transmitted over the line, by means of a key tobe manipulated by the operator, and received as dots ordashes, orotherwise; second, the maintenance of the continuity of the circuit ofthe main line whereby duplex working in such a system is renderedpossible.

In Letters Patent of the United States heretofore issued to me I haveshown atelegraphic system analogous to that herein disclosed, in whichcurrents of alternating polarity and approximately equal duration, aretransmitted over a line by the manipulation of an ordinary key, and arereceived as dots and dashes; and in which the line is put to earth aftereach impulse of current has been sent into it. Such a system is shown inmy Patents No. 373,967 of November 29, 1887; No. 373,968 of November 29,1887, and No. 388,481, of August 28, 1888. The apparatus shown in thesepatents while productive of very satisfactory results on difficultcircuits, is open to several objections which my present invention isdesigned to overcome: First, impulses of current of absolutely uniformduration cannot always be obtained as the duration is dependent more orless upon the manipulation of the key, and will, therefore, necessarilybe variable; second, by reason of the rapid flight of a trailing contactfinger connected with the line from one earth contact to another acrossthe face of an intermediate contact connected with the main battery,the

impulses of current sent into the circuit are too brief to makethemselves adequately manifest at the receiving end of a comparativelylong line; third, the opening of the circuit of the main line when thecontact maker or trailer passes from a battery segment to a groundsegment, th e objection to this arrangement being` that the opening ofthe line reuders duplex working diflicult and unsatisfactory, if notwholly impracticable. An attempt to remedy this defect by causing thetrailer to bridge from one contact to the other, would be objectionablebecause it would still further reduce the time or length of the impulsesent into the line from the battery segment.

In Letters Patent N o. 381,764, issued to me April 24, 1888, I haveshown a similar system of telegraphy, in which apparatus to increase theduration of the impulses is employed, but in that organization thereexists also the defeet that the succeeding impulses will, to a limitedextent, vary in duration, depending, as they do, upon the manipulationof the keys, and the circuit of the main lineis open at intervals, thusrendering duplex working` impracticable. By means of the organizationherein set forth the main circuit is at all times closed either throughthe transmitting battery or the line is connected to earth or the returnwire by a circuit connection outside of the battery. A longer time ofduration of contact or connection between the main line and thetransmitting battery is afforded, and a more perfect equalization ofduration of all the impulses sent into the line is attained. Bymaintaining the continuity of the circuit the line may readily beduplexed.

The advantage of sending impulses of current of alternating polarity andequal duration into the line as set forth in my patents above mentioned,are well known to those familiar with this class of telegraphy and needno further reiteration here.

In the accompanying drawings: Figure 1 is a diagrammatic viewillustrating the system, and Fig. 2 is a detail view of a polarizedrelay or transmitter, the movement of Whose armature determines theduration of the iinpulses sent into the line and the grounding of theline.

IOO

In the drawings the circuits are shown completed through the earth butof course all metallic circuits may be used under precisely similarconditions.

L is the main line, X a transmitting station and Y a receiving station.

At the receiving station P R is a polarized relay which may control thecircuit of a sounder or recorder, upon which the transmitted impulses ofequal duration Ymay be received as dots and dashes as set forth in myprior patents. At the sending station the line is connected to bothstops of the armature of the polarized transmitter P T and the armatureis permanently connected to earth. These stops are connected through aresistance R with two insulated yielding contacts k, Zt on each side ofthe pivot of the transmitting key K. The main battery M B is grounded inthe middle at E and practicallyY forms therefore two sources of currentand its two central orV earth connected poles are therefore connectedthrough the earth with the transmitter armature. Its opposite poles arerespectively connected -with the stops Z Z against which the contacts 7clo on the key work as the key is manipulated. The local battery L B thatoperates the polarized transmitter has its middle connected with oneterminal of the coils of Ythat transmitter. The opposite terminal ofsaid coils is connected with the key K, and the opposite poles of thelocal battery are respectively connected with the front and back stops'm m of the key. The parts are so constructed and related that whenthekey is depressed the insulated contact k thereon, and the contact Zconnected with one pole of the main battery are irst closed before thekey strikes its front stop m. In like manner when the key is raisedcontact is made between k and Z before the key comes against its backstop m. The effect of this organization is as follows: The apparatusbeing in condition for transmission and the key being up as indicated inthe drawings, the armature of the transmitter? T is against its stop t,the local circuit being closed on the back stop 'm of the transmittingkey. One pole of the main battery is connected through the contacts Z laand resistance R with the main line, and is also grounded through thearmature of the transmitter, the current from the battery beingtherefore shunted from the main line. When the key is depressed thelocal of the polarized transmitter is tirst opened; the connection withthe main battery is then broken at 7c Z; the opposite pole of thebattery is connected with the line and earth through the contacts Zt land finally the local of the polarized transmitter is completed at thecontact m and the armature of the transmitter is thrown to its stop t.W'hen the armature of the transmitter is against either of its contactsthe main battery is shunted from the line, but during the liight of thearmature from one contact to the other the shunt is broken and thecurrent from the battery M B passes to the line. It will be perceivedthat the main line circuit is never open but is always completed eitherthrough the armature of the polarized transmitter, or through the mainbattery M B. The resistance R may be adjusted to suit the conditions andrequirements of the circuit and is inserted for the purpose ofpreventing an undue depletion of the battery when it is shunted from themain line.

The length of time occupied by the armature-of the transmitter inpassing from one stop to the other after the closing of the circuit ofthe local. battery, and consequently the duration of the impulses sentinto the line, may be increased or diminished by the proper manipulationand adjustment of the local battery L B and the pole pieces of thepolarized transmitter, all as is well understood, and to this end also aresistance R may be placed in the local circuit. In order to render themovement of the armature ot' the transmitter sluggish and thus increasethe duration of the transmitted impulses a tension maybe put upon thearmature by means of a light spring O, so placed as to bear upon theupper edge of the armature. This spring may be adjustable by means of ascrew O. Fig. 2 shows this construction. Obviously any other means ofdelaying or retarding theV iiight of the armature yfrom one stop to theother maybe adopted. Many such means are well known to persons wellversed in telegraphic systems and their recital here is unnecessary.When Vthe key and polarized transmitter are once adj usted so that thearmature moves at the same time in either direction the duration of thetransmitted impulses will be unvarying and practically independent ofthe manipulation of the key. /Vhen the operator at X is not transmittingthe switch S would be turned so as to place the line L in connectionwith a wire leading to a receiver, this wire being marked in thedrawings To the receiver. The switch s would also be open so as to takethe ground off the battery. The static current from the line, that mayoccur when the current is withdrawn from the line by the establishmentof the shunt through the armature of the transmitter P T, will eitherdischarge, through said armature, to earth orhinto the other side ot thecircuit; or will be overcome by the current from the main battery. Thelatter might be the case if the resistance R were so adj usted as topermit suflicient current to enter the line when the armature is againstone of its stops.

I claim as my inventionl. The combination, substantially as set forth,of the transmitter armature, its stops, the main circuit connected withboth stops and extending to the distant receiver and back by the returnconnection to said armature, sources of currents of opposite polarityhaving each one pole connected with said ar- IOO IIO

mature, a transmitting key, battery contacts carried thereby, a circuitconnection between said contacts and the stops of the transmittingarmature, a resistance in said circuit connection, the local battery ofthe transmitter and its contacts, and circuit connections controlled bythe transmitting key.

2. The combination, substantially as set forth, of the transmitterarmature, its stops, a main circuit connected with both of said stopsand extending to the distant receiver and back by the return connectionto said armature, sources of currents of opposite polarity having eachone pole connected with said armature, and means for alternatelyconnecting such sources with the stops of the transmitter armature andcoincidently effecting the movement of the armature from one of itsstops to the other, whereby alternating currents enter the line duringthe Iiights of the armature from one stop to the other.

3. The combination, substantially as set forth, of the transmitterarmature, its adjustable stops, a main line connected with both of saidstops, sources of currents of opposite polarity, each having one poleconnected with said armature, and means for alternately connecting theopposite poles of such sources with the stops of the transmitterarmature and coincidently effecting the movement of the armature fromone of its stops to the other, whereby alternating currents enter theline during the iiights of the armature from one stop to the other.

4. The combination, substantially as set forth, of the transmitterarmature, its stops, a main line connected with both of said stops,sources of currents of opposite polarity, each having one pole connectedwith said armature means for alternately connecting the opposite polesof such sources with the stops of the transmitter armature andcoincidently effecting the movement of the armature from one of itsstops to the other, whereby alternating currents enter the line duringthe iiights of the armature from one stop to the other, and means forregulating the duration of the iiight of the armature.

In testimony whereof I have hereunto subscribed my name.

PATRICK BERNARD DELANY.

Witnesses:

EDWARD C. DAVIDSON, M. J. KELLEY.

